The physical properties of crystalline iron-rich silicides

• Published in: Physics letters. A Vol. 524; p. 129819
• Main Authors: Wang, Yanming, Xu, Ruichen, An, Xiaofei, Zang, Yubo, Guan, Hongyu, Yu, Guoliang, Zhang, Xinxin, Cheng, Taimin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.11.2024
• Subjects: Crystalline iron-rich silicides; Electronic and magnetic properties; first-principles calculations; Lattice dynamics; Mechanical Properties; first-principles calculations; Crystalline iron-rich silicides; Mechanical Properties; Electronic and magnetic properties; Lattice dynamics
• ISSN: 0375-9601
• DOI: 10.1016/j.physleta.2024.129819

•The physical properties of several complex Fe-Si phases are studied by DFT.•The structural stability is verified by formation enthalpy, phonon and elastic constants.•The magnetic, electronic, and mechanical properties are discussed.•Anomalous phonon behavior is observed in the Fe24Si5 phase.•The Young's modulus, shear modulus and Debye temperature decrease with the increase of Fe/Si ratio. The formation enthalpy, electronic structure, lattice dynamics and elasticity of several complex ordered iron-rich silicides (Fe11Si5, Fe13Si3, Fe17Si12 and Fe24Si5) are calculated from the first-principles calculations. It is found that the Debye temperature ΘD of the system decreases with the increase of the ratio of the number of iron atoms to the number of silicon atoms in the same structure. The softening of low-energy acoustic phonons is more obvious with the increase of iron atoms. The elastic constants C11 and C44, Young's modulus E and shear modulus G of the system decrease with the increase of iron atoms. An anomalous phenomenon occurs in the high frequency region of Fe24Si5. The contribution of Fe1 atoms with smaller magnetic moment to the phonon density of states is much larger than that of the Si and other Fe atoms. This indicates that the local metal bond strength between Fe1-Fe1 atoms is stronger.